AFR is leaner with larger injectors...Any thoughts????

Here's the setup on our first three runs:
04 RXP
X-Charger
Riva Air Intake
Stock injectors
Stock impeller
For the above the LM-1 readings on all three runs were very consistent at AFR 12.9 turning 8150rpm.

Changed the injectors to 42's added pump wedge then made two runs.
AFR for both runs were 14.0 at 8150.

The only thing that makes any sense to me is the injectors can not be 42's?

Here's the setup on our first three runs:
04 RXP
X-Charger
Riva Air Intake
Stock injectors
Stock impeller
For the above the LM-1 readings on all three runs were very consistent at AFR 12.9 turning 8150rpm.

Changed the injectors to 42's added pump wedge then made two runs.
AFR for both runs were 14.0 at 8150.

The only thing that makes any sense to me is the injectors can not be 42's?

Any thoughts greatly appreciated.

do you have a rrfpr if so what is it set at. if you dont have one you need to get one.

Here's the setup on our first three runs:
04 RXP
X-Charger
Riva Air Intake
Stock injectors
Stock impeller
For the above the LM-1 readings on all three runs were very consistent at AFR 12.9 turning 8150rpm.

Changed the injectors to 42's added pump wedge then made two runs.
AFR for both runs were 14.0 at 8150.

The only thing that makes any sense to me is the injectors can not be 42's?

Any thoughts greatly appreciated.

There is a possibilty that with the extra power you would make with additional fuel you were going hard into the limiter, Being in the limiter will make you lean. R88

Thanks for the thoughts on the leaning out issue.
I will post a pic of the injectors.
I was planning to change the impeller to a 15/20, will do and advise.

However, I quick question. If I'm banging the rev limiter, shouldn't I see a lean spike on the LM-1 plot indicating lots of air since none was used in combustion. I'm assuming the rev limiter will not allow spark when it triggers. Am I thinking right on this?

The first 3 passes showed this large AFR spike on the lm-1 plat with the 38's, I didn't think till now this maybe indicating that I'm on the rev limiter.

... If I'm banging the rev limiter, shouldn't I see a lean spike on the LM-1 plot indicating lots of air since none was used in combustion. I'm assuming the rev limiter will not allow spark when it triggers. Am I thinking right on this?

These ECU's start pulling out cylinders periodically starting around 8150 but doesn't pull them all til around 8350. It's truly a "soft" limiter. If it's only pulling every 8th combustion cycle, it will show up as leaner the whole time since the gasses mix in the manifold.

These ECU's start pulling out cylinders periodically starting around 8150 but doesn't pull them all til around 8350. It's truly a "soft" limiter. If it's only pulling every 8th combustion cycle, it will show up as leaner the whole time since the gasses mix in the manifold.